Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04637 (p53)
 77,613 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report here the isolation and identification of the RNA specifically immunoprecipitated and covalently linked to the tumor suppressor gene product p53. After treatment with proteinase K, the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) band of p53 yields a single, discrete 157-nucleotide RNA, which was cloned, sequenced, and identified as 5.8S rRNA. 5.8S rRNA was obtained only after proteolysis of the p53 SDS-PAGE band. Free 5.8S rRNA did not comigrate with p53 in SDS-PAGE. This RNA was only immunoprecipitated from cells containing p53. Protein-free RNA obtained by proteolysis of the p53 band hybridized to the single-stranded DNA vector containing the antisense sequence of 5.8S rRNA. The covalence of the p53-5.8S rRNA linkage was demonstrated by the following findings: (i) p53 and the linked 5.8S rRNA comigrated in SDS-PAGE; (ii) only after treatment of the p53-RNA complex with proteinase K did the 5.8S rRNA migrate differently from p53-linked 5.8S rRNA; and (iii) this isolated RNA was found linked to phosphoserine, presumably at the 5' end. Covalent linkage to the single, specific RNA suggests that p53 may be involved in regulating the expression or function of 5.8S rRNA.
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PMID:p53 is covalently linked to 5.8S rRNA. 140 86

DNA from archival Papanicolaou stained smears was successfully amplified using the polymerase chain reaction (PCR) to see if it could be used for retrospective genome studies such as detection of the presence of human papilloma virus (HPV) and changes in p53 gene expression. DNA was isolated and purified by treatment with proteinase K, phenol/chloroform, and isoamyl alcohol. Segments of the human beta actin and TGF beta 1 gene were amplified by PCR. Of all stains used in the preparation of Papanicolaou smears, only eosin was detectable as a greenish band in ethidium bromide treated DNA gels under ultraviolet illumination.
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PMID:PCR amplification of DNA from stained cytological smears. 768 6

We have studied the roles of Ki-ras oncogene and p53 tumor suppressor gene in a series of 20 cases of male breast cancer and one papilloma of the male breast. Ki-ras was detected in 50-microns sections after digestion with proteinase K and SDS. DNA was amplified by polymerase chain reaction, dot blotted, and mutations were screened with labeled ras mutation-specific oligonucleotides. Wild-type and mutant p53 protein were detected with antibodies CM1 and DO7, using the avidin-biotin-peroxidase method. Two of 17 carcinomas showed Ki-ras mutations, both in codon 12 (gly --> lys and gly --> arg). Five of 20 male breast cancers (25%), including one large intraductal carcinoma, expressed mutant p53 protein. Although the incidence of mutant p53 expression in male breast cancer is similar to that in women, Ki-ras mutations are not significantly increased.
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PMID:ras and p53 genes in male breast cancer. 872 73

We studied the role of proteases in apoptosis using a cell-free system prepared from a human leukemia cell line. HL60 cells are p53 null and extremely sensitive to a variety of apoptotic stimuli including DNA damage induced by the topoisomerase I inhibitor, camptothecin. We measured DNA fragmentation induced in isolated nuclei by cytosolic extracts using a filter elution assay. Cytosol from camptothecin-treated HL60 cells induced internucleosomal DNA fragmentation in nuclei from untreated cells. This fragmentation was suppressed by serine protease inhibitors. Serine proteases (trypsin, endoproteinase Glu-C, chymotrypsin A, and proteinase K) and papain by themselves induced DNA fragmentation in naive nuclei. This effect was enhanced in the presence of cytosol from untreated cells. Cysteine protease inhibitors (E-64, leupeptin, Ac-YVAD-CHO [ICE inhibitor]) did not affect camptothecin-induced DNA fragmentation. The apopain/Yama inhibitor, Ac-DEVD-CHO, and the proteasome inhibitor, MG-132, were also inactive both in the cell-free system and in whole cells. Interleukin-1 beta converting enzyme (ICE) or human immunodeficiency virus protease failed to induce DNA fragmentation in naive nuclei. Together, these results suggest that DNA damage activates serine protease(s) which in turn activate(s) nuclear endonuclease(s) during apoptosis in HL60 cells.
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PMID:DNA fragmentation induced by protease activation in p53-null human leukemia HL60 cells undergoing apoptosis following treatment with the topoisomerase I inhibitor camptothecin: cell-free system studies. 880 33

DNA was extracted from unstained 5-microns sections of neutral buffered 10% formalin-fixed paraffin-embedded tissue by proteinase K digestion without detergents followed by boiling, proteinase K digestion with ionic detergents with and without phenol chloroform extraction and ethanol precipitation, sonication with proteinase K followed by boiling, or boiling alone. Serial 1:10 dilutions of the extracted DNA were subject to polymerase chain reaction (PCR) amplification of a 255-bp portion of the p53 gene. Digestion with proteinase K without ionic detergents followed by boiling (without phenol chloroform extraction) gave the best yield, enabling visualization of ethidium bromide-stained PCR product from a DNA dilution corresponding to 0.1 mm2 of tissue containing of the order of 10(3) nuclear profiles. Proteinase K digestion with detergents followed by phenol-chloroform extraction was no more effective than simple boiling. Although the success of PCR from preserved tissue will vary with the fixative and size of the amplified fragment, DNA extracted with this optimized method can be used for identification of viruses, loss of heterozygosity, and immunoglobulin gene rearrangements in paraffin-embedded tissue without radioisotopes.
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PMID:Comparison of methods for extracting DNA from formalin-fixed paraffin sections for nonisotopic PCR. 886 37

Our previous finding that the tumor suppressor p53 is covalently linked to 5.8S rRNA suggested functional association of p53 polypeptide with ribosomes. p53 polypeptide is expressed at low basal levels in the cytoplasm of normal growing cells in the G1 phase of the cell cycle. We report here that cytoplasmic wild-type p53 polypeptide from both rat embryo fibroblasts and MCF7 cells and the A135V transforming mutant p53 polypeptide were found associated with ribosomes to various extents. Treatment of cytoplasmic extracts with RNase or puromycin in the presence of high salt, both of which are known to disrupt ribosomal function, dissociated p53 polypeptide from the ribosomes. In immunoprecipitates of p53 polypeptide-associated ribosomes, 5.8S rRNA was detectable only after proteinase K treatment, indicating all of the 5.8S rRNA in p53-associated ribosomes is covalently linked to protein. While 5.8S rRNA linked to protein was found in the immunoprecipitates of either wild-type or A135V mutant p53 polypeptide associated with ribosomes, little 5.8S rRNA was found in the immunoprecipitates of the slowly sedimenting p53 polypeptide, which was not associated with ribosomes. In contrast, 5.8S rRNA was liberated from bulk ribosomes by 1% sodium dodecyl sulfate, without digestion with proteinase K, indicating that these ribosomes contain 5.8S rRNA, which is not linked to protein. Immunoprecipitation of p53 polypeptide coprecipitated a small fraction of ribosomes. p53 mRNA immunoprecipitated with cytoplasmic p53 polypeptide, while GAPDH mRNA did not. These results show that cytoplasmic p53 polypeptide is associated with a subset of ribosomes, having covalently modified 5.8S rRNA.
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PMID:Cytoplasmic p53 polypeptide is associated with ribosomes. 915 13

The pathogenesis of carcinosarcoma is still a subject of controversy. In the present study, molecular techniques were applied to determine the pathogenesis of uterine carcinosarcomas. The patterns of chromosome X inactivation were analyzed, targeting a portion of exon 1 of the human androgen receptor (HUMARA) in malignant epithelial and mesenchymal components. The presence of p53 and K-ras mutations were also analyzed. H&E-stained sections of paraffin-embedded, formalin-fixed tissues were microdissected to obtain both epithelial and nonepithelial lesions from 25 carcinosarcomas, and DNAs were extracted by proteinase K digestion. Following treatment with methylation-sensitive restriction endonuclease (HhaI or HpaII), PCR amplification was performed using nested primers targeted to the HUMARA locus. Mutations in the p53 gene and K-ras gene were found in eight (32%) and six (24%) tumors, respectively. The patterns of chromosome X inactivation were different between the carcinomatous and sarcomatous components of three carcinosarcomas, indicating that these three tumors represent collision tumors. By contrast, the patterns of chromosome X inactivation, K-ras sequence, and p53 sequence were identical in both carcinomatous and sarcomatous components in 21 carcinosarcomas, indicating that these 21 tumors represent combination tumors. One case produced equivocal results that precluded determination of whether it represented a collision or combination tumor. These observations show that although most carcinosarcomas are combination tumors, some develop as collision tumors. The determination of histogenesis in individual cases of carcinosarcoma using molecular markers may be worthwhile, because the result could help predict the prognosis of individual cases and help guide clinical management.
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PMID:Molecular evidence that most but not all carcinosarcomas of the uterus are combination tumors. 939 63

A method to detect shed virus in patients' serum and urine was developed following Ad5CMV-p53 gene transfer via direct tumor injections. The procedure differs from those reported previously in that it first uses polyethylene glycol to precipitate adenoviral particles from patient serum or urine. Adenoviral DNA is then extracted following proteinase K digestion. Finally, polymerase chain reaction (PCR) amplification followed by Southern blot transfer are employed to enhance the limit of detection to less than ten viral particles. The detection limit in a 0.25-ml sample is five viral particles in serum and one viral particle in urine. This procedure is sensitive, reproducible, and can be completed in less than 2 days.
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PMID:A simple and sensitive method for detecting adenovirus in serum and urine. 962 21

The histogenesis of carcinosarcoma of the breast is controversial. In the current case, the demarcation between the carcinomatous and sarcomatous components was distinct in all microscopic fields. Immunohistochemical analysis was negative for epithelial membrane antigen (EMA) and keratin in the sarcomatous component and was negative for desmin in the carcinomatous component, suggesting that this tumor could be derived from the two different stem cells. To determine the histogenesis of this tumor, both carcinomatous and sarcomatous lesions were microdissected from formalin-fixed tissues and DNAs were prepared by proteinase K digestion. PCR amplification of the human androgen receptor (HUMARA) short tandem repeat (STR), after Hpa II digestion of the genomic DNA, indicated that the patterns of X-chromosome inactivation were identical in both components. Moreover, both components contained the identical TGT --> TTT transversion in codon 275 of the p53 gene. These observations strongly support the hypothesis that this tumor is derived from a single totipotent stem cell.
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PMID:Carcinosarcoma of the breast: molecular-biological study for analysis of histogenesis. 982 16

Alterations to p53 seem to be of prognostic significance in soft tissue sarcomas, but their significance for synovial sarcomas has not been studied. We analysed 34 synovial sarcomas in 19 patients for p53 alterations (p53 gene mutations + p53 immunopositivity) and examined this factor for its prognostic value in a group of 15 primary tumours. DNA was prepared from paraffin-embedded tumour material by a modified proteinase K/phenol/chloroform extraction. p53 gene mutations of exons 5-8 were analysed by the PCR-SSCP-sequencing method. p53 protein expression was evaluated by immunohistochemistry using the murine monoclonal antibody DO1. We found two missense mutations (5.9%) and ten p53 immunopositive cases (29.4%). Both tumours with p53 mutations showed p53 protein expression. There was no significant correlation between p53 alteration and histological subtype, age, sex, or tumour size. The 5-year survival rate was 24.1%. Overall survival was significantly reduced in patients having synovial sarcomas with p53 alterations (P<0.001). In the multivariate Cox's analysis, only p53 alterations (P=0.032) and tumour size (P=0.023) emerged as independent prognostic factors. We suggest that p53 alterations may be a useful prognostic indicator in synovial sarcomas, allowing rational clinical treatment and follow-up.
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PMID:Prognostic significance of p53 gene mutations and p53 protein expression in synovial sarcomas. 1052 4


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